A gyratory crusher of the type stated above can be used for crushing, for example, ore and stone material into smaller-size particles.
WO 99/22869 discloses a gyratory crusher, in which a crushing head is mounted on a gyrating vertical shaft. At its lower end, the vertical shaft is supported by a thrust bearing including three horizontal bearing plates. A first bearing plate is fastened to the vertical shaft, a second bearing plate is fastened to a piston arranged below the vertical shaft, and a third bearing plate is slideably and rotatably arranged between the first and the second bearing plate. The first and second bearing plates are generally made of a bearing metal, such as bronze, and the third bearing plate is often made of steel. The piston arranged below the vertical shaft forms, together with a cylinder, a hydraulic piston arrangement by way of which the vertical position of the vertical shaft can be displaced for the purpose of setting a desired crushing gap between the first and the second crushing shell.
WO 2006/067277 discloses a gyratory crusher in which a crushing head rotates about an immobile vertical shaft. Inside the crushing head, a piston and a cylinder are arranged, which together form a hydraulic piston arrangement. The crushing head may either include a cylinder or, according to an alternative embodiment, support a piston. The complementary piston or, according to the alternative embodiment, cylinder rests on a thrust bearing supported by the upper portion of the vertical shaft. The thrust bearing consists of a first horizontal bearing plate, which is fastened to the piston, alternatively to the cylinder, and a second horizontal beating plate, which is fastened to the upper portion of the vertical shaft.
A drawback of both of the crushers described above is that the existing types of thrust bearings are expensive and the horizontal bearing plates included therein are subjected to considerable wear, which necessitates frequent changes of the thrust bearings at a high cost.